.content {
  position: relative;
  width: 100vw;
  height: 100vh;
  background-color: antiquewhite;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  .header {
    position: absolute;
    top: 0%;
    width: 100%;
    height: 100px;
    line-height: 100px;
    text-align: center;
    background-color: rgba(21,20,13,0.5);
    h3 {
      width: 100%;
      color: white;
      font-size: 30px;
    }
  }
  .login-box {
    position: relative;
    width: 400px;
    height: 400px;
    background-color: rgba(74,0,170,0.3);
    border-radius: 30px;
    color: white;
    display: flex;
    flex-direction: column;
    align-items: center;
    h1 {
      color: white;
      margin: 50px 0 10px 0;
      font-size: 36px;
    }
    .output-form {
      margin-top: 20px;
      width: 300px;
      height: 40px;
      display: flex;
    }
  }
}
.content::before {
  position: absolute;
  content: "";
  display: block;
  width: 300%;
  height: 100%;
  background-image: linear-gradient(to bottom right,rgb(25,0,255),rgb(111,0,255),rgb(242,0,250));
  filter: blur(4px);
  animation: bg-anim 3s alternate infinite linear;
}

@keyframes bg-anim {
  from {
    left: 0;
  }
  to {
    left: -200%;
  }
}